Identification of materials



instance, in dry cleaning establishments.

Patented Dec. 11, 1945 UNITED STATES PATENT": OFFICE IDENTIFICATION OF MATERIALS Benjamin W. Collins, Swarthmore, Pa., assignor to American Viscose Corporation, Wilmington, Del., a corporation of Delaware No Drawing. Application August 14, 1941,

- Serial No. 400,917

20 Claims. 7 (61. 106-165) This invention relates to the manufacture of synthetic yarns and other shapes containing a foreign substance, by means of which they may be readily identified, and is a continuation-inpart of my copending application Serial No. 242,282, filed November 25, 1938, now Patent 2,256,549, issued September 23, 1941.

His desirable to be able to identify the origin and method of manufacture. of synthetic yarns and other shapes. This is often not easy to do, howevenfor the ordinary means of identification are not permanent/and do not give positive results.

It is, therefore, an object of this invention to provide a method of positively identifying the origin and method of manufacture of synthetic yarns and other shapes.

Other objects and advantages of this invention will become apparent from the following description and appended claims.

Methods of identifying rayon yarns and other shapes have been suggested in the United States patent to- Whitehead 1,885,878. However, the

' class of foreign substances mentioned in the Whitehead patent are not entirely suitable for identification purposes in synthetic yarns or terlal from which the synthetic yarn or shape is made, in the form of exceedingly finely divided suspensions in which the diameter of the larger thermore, as a means of providing a permanently and uniformly distributed identifying material,

the insoluble particles offer the added advantage other shapes, particularly those produced by.

regenerating cellulose from a cellulose solution. Such compounds as nickel and strontium chloride that are disclosed in the patent as being typical examples of identifying substances are readily soluble in water. By the same token they are readily leached out either during the aqueous treatment required in the manufacture and finishing of synthetic yarns or other shapes or during the subsequent processes to which such goods are commonlysubjected, such as kier boiling, dyeing, sizing, soft finishing, and also ordinary laundering in the hands of the ultimate con- In contradistinction to this procedure, I have found that as a class, the most valuable identifying substances are those possessing the highest degree of insolubility in water as well as in solu tions of acids, alkalies, desulphiding agents, bleaching agents,.soaps, oils, or oily emulsions as well as organic solvents such as may b used, for

Furthermore, I have found that substances possessing such highly desirable characteristics may be mooessfully introduced into the solution of ma.

of remaining firmly fixed in the yarn or shape. They cannot be washed away or moved from their original positions as is true in the case of soluble compounds which exhibit definite tendencie to localize or concentrate in the lower portions of skeins or fabrics hung up to dry.

Having described the advantages of such highly insoluble materials, I now cite several typical examples and will describe in greater detail methods for their successful introduction into the viscose process. I may employ, by way of illustration, insoluble substances comprising compounds of gold, copper, silver, lithium, barium, cadmium, beryllium, lanthanum, boron, tin, thorium, cerium, zirconium, bismuth, arsenic, antimony, tantalum, uranium,- chromium, molybdenum, tungsten, cobalt, praseodymium and neodymium; such as the silicates of these metals, the oxides of beryllium, zirconium, bismuth, tantalum-chromium, molybdenum and tungsten; such organic derivatives as the oleates, stearates and laurates of copper, silver, barium, cadmium, beryllium, tin, zirconium, bismuth, chromium, andcobalt; and various glasses to which these metals or compounds thereof have been added. I may also employ the naturally occurring mineral ores such as spodumene, whichis a double silicate of aluminum and lithium; tourmaline, which is usually a combination of lithium, sodium, potassium, iron, magnesium, and manganese silicates; cerite,

which contains silicates of cerium and allied materials; gadolinite, which usually contains silicates of iron, beryllium, yttrium, cerium and erbium; and monazite, which usually contains silicates, phosphates of certain rare elements such as cerium, neodymium, praseodymium, lanthanum and thorium. These substances maybe used separately or several of them together.

All}! fiiimciently insoluble cmnpound of any of these or similar metallic bases may be reduced in.

. subjected to thorough mechanical mixing to distribute them uniformly throughout the cellulose solution.

I prefer to add the very smallest amount of the substance compatible with'positive identification requirements, which may vary from less than 1 part to 5 parts of the identifying substance per million partsby weight of the finished yarn or shape. Particles of this order of magnitude and in the very small amounts that are used do not change the physical characteristics or'perceptible general appearance of the yarns or shapes produced. It is found that it requires about 1200 parts or foreign substance per million parts of the yarn or shape in order to effect a perceptible change in their general appearance.

Obviously the laboratory procedures for effecting the identification of synthetic products produced in this manner will vary according to whichever may be the most sensitive characteristic reaction of the substance in, question. The amounts of the substance used may be propora characteristic precipitate or the result of a spectographic analysis.

While I fin d that the above examples give the most desirable results, I do not wish to be limited toonly these, for my invention covers the use ,of other insoluble compounds as well. Also although the invention has been described in connection with the viscose process, it is to be understood that it is applicable equally as well to other synthetic yarns and shapes of essentially organic materials including cellulosic materials, such as cellulose acetate and resinous materials, such as copolymers of vinyl chloride and vinyl acetate.

What I claim is:

1. A solution of an organic filament-forming material capable Of being formed into artificial filaments, yarns, and other shaped structures containing in an amount insuflicient to change the perceptible. general characteristics of the shaped structure, of the order of less than'l200 parts thereof per million parts of the structure,

a material by which the shape may be identified comprising an i soluble metal silicate.

. shaped structure, of the order of less than 1200 I tioned to the sensitiveness of the identification procedure, whether it be a delicate color reaction,

v2. Artificial filaments comprising mainly an organic material containing less than 1200 parts of an insoluble metal silicate per million parts of the filaments.

3. A cellulosic solution for the production of filaments. yarns, and other shaped structures containing in an amount' insufllcient to change the perceptible general characteristics of the shaped structure, of the order of less than 1200 parts thereof per million parts of the structure,

' a material by which th shape may be identified comprising an insoluble metal silicate.

4. Artificial cellulosic filaments containing less than 1200 parts of an insoluble metal silicate per million parts of the filaments.

5. A cellulosic solution for the production of filaments, yarns, and other shaped structures containing in an amount insufllcient to change the perceptible general characteristics 01 t e parts thereof per million parts of the structure, a material by which the shape may be identified comprising an insoluble metal silicate having the composition of a glass.

6. Artificial cellulosic filaments containing less ring mineral silicate per million parts of the filaments.

9. A solution of an organic filament-forming material capable of being formed into artificial filaments, yarns, and other shaped structures containing in an amount insufficient to change the perceptible general characteristics of the shaped structure, of the order of less than 1200 parts thereof per million parts of the structure, a material by which the shape may 'be identified comprising beryllium silicate.

10. A solution of an organic filament-forming ,material capable of beingformed into artificial filaments, yarns, and other shaped structures containing in an amount insufficient to change the perceptible general characteristics of the shaped structure, of the order of less than 1200 parts thereof per million parts of the structure, a material by'which the shape may be identified comprising zirconium silicate.

11. A solution of an organic filament-forming material capable of being formed into artificial filaments, yarns, and other shaped structures containing in an amount insufllcient to change the perceptible general characteristics of the shaped structure, of the. order of less than 1200 parts thereof per million parts of the structure, a material by which the shape may be identified comprising molybdenum silicate.

12. Artificial filaments comprising mainly an organic material containing less than 1200 parts of beryllium silicate per million parts of the fila- 13. Artificial filaments comprising mainly an organic material containing less than 1200 parts of zirconium silicate per million parts of the filaments.

14. Artificial filaments comprising mainly an organic material containing less than 1200 parts of molybdenum silicate per millionparts of the filaments.

15. Regenerated cellulose filaments containing less than 1200 parts of beryllium silicate per million parts of the filaments.

16. Regenerated cellulose filaments containing less than 1200 parts of zirconium silicate per million parts of the filaments.

17. Regenerated cellulose filaments less than 1200 parts of molybdenum silicate per million parts of the filaments.

18. A cellulosic spinning solution for the pr duction of cellulosic shapes containing in an amount insuificient to change the perceptible general characteristics of th shape, of'the order of less than 1200 parts per million parts of the shape,

containing I a material by which the shape may be identified comprising zirconium silicate.

-19. A cellulosic spinning solution for the production of cellulosic shapes containing in an amount insuflicient to change the perceptible general characteristics of the shape, of the order of less than 1200 parts per million parts of the shape, a material by which the shape may be identified comprising beryllium silicate.

BENJAMIN W. COLLINS. 

